1. Field of the Invention:
The present invention relates to a joint socket device for memory cards, and particularly to a socket device, which is possible for being inserted with a smart media card (SMC), a multimedia card (MMC), a secure digital memory card (SD) and a memory stick (MS) respectively.
2. Description of Related Art:
Usually, a portable personal apparatus such as a digital camera or a notebook computer is provided with a memory card for storing data. It is necessary to arrange a socket device to receive the memory card of the portable personal apparatus. The socket device provides a conduction part to connect with the memory card and a microprocessor in the portable personal apparatus. Referring to FIG. 1, a SMC 10 is a large card with a small thickness, a MMC 20 is smaller and thicker, a SD 30 has the same area as the MMC 20 but much thicker, and the MS 40 has the smallest width and the largest length with a largest thickness. Each of the four memory cards at a facial side thereof is barely attached with different numbers of connection pieces 101, 201, 301, 401. The connection pieces are passages for the memories in the memory cards in conjunction with foreign parts. Each of the connection pieces 101 of the SMC 10 has almost the same width as that of the respective connection piece 201 of the MMC 20 and a clearance between two neighboring connection pieces 101 is almost the same as that between two neighboring connection pieces 201. The SD 30 has the connection pieces 301 thereof in a recess and a clearance between two adjacent ones for the 7 pieces at the middle section thereof is the same as that between two neighboring connection pieces 201 thereof. The connection pieces 401 of the MS 40 are also in a recess and provide a narrowest clearance between two adjacent ones thereof. All the four memory cards have a cut corner 102, 202, 302, 402 respectively, the SD 30 further has a write protect switch 303, and the MS 40 further has an anti-reversed insertion groove 403. Because SMC 10, MMC 20, SD 30 and MS 40 provide a shape, size and the number of junctions thereof different from one another, the socket devices adapted to the preceding memory cards are different from one another in their configurations and in the number of conduction parts thereof. The conventional socket device is only made for one of the preceding memory cards and not for all kinds of memory cards so that it is inconvenient that more socket devices have to be offered in case of multiple types memory cards being used. In this way, more joints have to be arranged in the circuit of each conventional socket device and a large space has to be offered for the multiple socket devices too.
An object of the present invention is to provide a joint socket device for memory cards, which is adapted to different types of memory cards to enhance the convenience while in use.
Another object of the present invention is to provide a joint socket device for memory cards, which offers less connection points and a less gross size thereof than the conventional ones having the identical functions.